Nectarine tree named &#39;Polar Snow&#39;

ABSTRACT

A new and distinct variety of nectarine tree ( Prunus persica  var.  nucipersica ). The following features of the tree and its fruit are characterized with the tree budded on ‘Nemaguard’ Rootstock (non-patented), grown on Handford sandy loam soil with Storie Index rating 95, in USDA Hardiness Zone 9, near Modesto, Calif., with standard commercial fruit growing practices, such as pruning, thinning, spraying, irrigation and fertilization. Its novelty consist of the following combination of desirable features:
     1. Tree with vigorous, upright growth.   2. Regular and productive bearer of large size fruit.   3. Fruit with a high degree of red skin color.   4. Fruit with firm, white flesh and excellent eating quality.   5. Fruit with good handling and shipping quality.

BOTANICAL DESIGNATION

Prunus persica var. nucipersica

VARIETY DENOMINATION

‘Polar Snow’

BACKGROUND OF THE VARIETY FIELD OF THE INVENTION

In the field of plant genetics, we conduct an extensive and continuingplant-breeding program including the organization and asexualreproduction of orchard trees, and of which plums, peaches, nectarines,apricots, cherries, almonds and interspecifics are exemplary. It wasagainst this background of our activities that the present variety ofnectarine tree was originated and asexually reproduced by us in ourexperimental orchard located near Modesto, Stanislaus County, Calif.

PRIOR VARIETIES

Among the existing varieties of nectarine trees, which are known to us,and mentioned herein, ‘Arctic Snow’ Nectarine (U.S. Plant Pat. No.7,920).

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT

Not applicable.

ORIGIN OF THE VARIETY

The new and distinct variety of nectarine tree (Prunus persica var.nucipersica) was originated by us in our experimental orchard locatednear Modesto, Calif. as a seedling selection from seed of unknownparentage. This selected seedling was grown and then budded onto olderestablished trees of ‘Nemaguard’ Rootstock (non-patented) to enhanceearlier fruit production. Under close and careful observation thepresent seedling exhibited desirable fruit and tree characteristics andwas selected in 2008 for additional asexual propagation andcommercialization.

ASEXUAL REPRODUCTION OF THE VARIETY

In 2008 asexual reproduction of the new and distinct variety ofnectarine tree was by budding to ‘Nemaguard’ Rootstock (non-patented),as performed by us in our experimental orchard located near Modesto,Calif., and shows that reproductions run true to the original tree andall characteristics of the tree and its fruit are established andtransmitted through succeeding asexual propagations.

SUMMARY OF THE NEW VARIETY

The present new variety of nectarine tree (Prunus persica var.nucipersica) is of large size, vigorous, upright growth and a productiveand regular bearer of large size, white flesh, clingstone fruit. Thefruit is further characterized by having a mild, sweet, sub-acid flavorwith excellent eating quality. In comparison to the commercial variety‘Arctic Snow’ Nectarine (U.S. Plant Pat. No. 7,920) the fruit of the newvariety is clingstone instead of freestone and is approximately 17 daysearlier in maturity.

DESCRIPTION OF PHOTOGRAPH

The accompanying color photographic illustration shows typical specimensof the foliage and fruit of the present new nectarine variety. Theillustration shows the upper and lower surface of the leaves, anexterior and sectional view of a single fruit divided in its sutureplane to show flesh color, pit cavity and the stone remaining in place.The photographic illustration was taken shortly after being picked(shipping ripe) from a 7 year old tree and the colors are as nearly trueas is reasonably possible in a color representation of this type.

DESCRIPTION OF THE VARIETY

The following is a detailed botanical description of the new variety ofnectarine tree, its flowers, foliage and fruit, as based on observationsof 7 year old specimens grown near Modesto, Calif., with color inaccordance with Munsell Book of Color published in 1958.

-   Tree:    -   -   Size.—Large, usually pruned to 3 to 3.5 meters in height and            width for economical harvesting of fruit. Size varies with            different cultural practices.        -   Vigor.—Vigorous, growth of 1.5 to 2 meters the first growing            season. Varies slightly with type and fertility of soil,            climatic conditions and cultural practices.        -   Form.—Upright, usually pruned to vase shape.        -   Branching habit.—Upright, crotch angle approximately 35°,            increases with heavy crop load.        -   Productivity.—Productive, thinning and spacing necessary for            desired market size fruit. Number of fruit set varies with            climatic conditions during blooming period.        -   Bearer.—Regular, has had adequate fruit set 5 consecutive            years. No alternate bearing observed.        -   Fertility.—Self fertile.        -   Density.—Medium dense, usually pruned to vase shape to            increase air movement and sunlight to center of tree to            enhance fruit color and health of fruit wood.        -   Hardiness.—Hardy in all stone fruit growing areas of            California. Tree grown in USDA Hardiness Zone 9. Winter            chilling requirement approximately 800 hours at or below 45°            F.-   Trunk:    -   -   Size.—Large. Average circumference 53.3 cm at 25.4 cm above            ground on a 7 year old tree.        -   Stocky.—Medium stocky.        -   Texture.—Medium shaggy, roughness increases with age.        -   Color.—Varies from 2.5Y 6/2 to 5Y 7/2.-   Branches:    -   -   Size.—Medium. Average circumference 17.8 cm at 1.2 meters            above ground. Crotch angle approximately 35°, increases with            heavy cop load.        -   Surface texture.—New growth relatively smooth. Mature growth            medium rough, roughness increases with age.        -   Lenticels.—Average number 15 in a 25.8 square cm area.            Average length 4.5 mm. Average width 1.9 mm. Color varies            from 10YR 4/2 to 2.5Y 5/2.        -   Color.—New growth varies from 5GY 6/8 to 5GY 5/8. Mature            growth varies from 2.5Y 4/4 to 2.5Y 3/4, varies with age of            growth.-   Leaves:    -   -   Size.—Large. Average length 143.7 mm. Average width 38.9 mm.        -   Form.—Lanceolate.        -   Apex.—Acuminate.        -   Base.—Cuneate.        -   Margin.—Serrate.        -   Thickness.—Medium.        -   Surface texture.—Upper surface relatively smooth, slight            indentations over midrib and leaf veins. Lower surface            relatively smooth, except for small ridges created by midrib            and pinnate venation. Both upper and lower surfaces            glabrous.        -   Petiole.—Average length 10.0 mm. Average width 1.8 mm.            Longitudinally grooved. Surface — glabrous. Color varies            from 2.5GY 6/6 to 2.5GY 5/6.        -   Glands.—Type — reniform. Size — small to medium. Average            length 1.3 mm. Average diameter 0.9 mm. Number varies from 2            to 4, average number 3. Located primarily on the base of            leaf blade and upper portion of the petiole. Color varies            from 2.5GY 5/6 to 2.5GY 6/7.        -   Stipules.—Average number 2. Average length 6.7 mm. Edges            pectinate. Color varies from 2.5GY 5/6 to 2.5GY 5/8.        -   Color.—Upper surface varies from 5GY 3/6 to 7.5GY 4/4. Lower            surface varies from 7.5GY 5/4 to 7.5GY 4/4. Midvein color            varies from 10Y 8/4 to 2.5GY 8/4.-   Flower buds:    -   -   Size.—Large. Average length 20.4 mm. Average diameter 11.8            mm.        -   Hardiness.—Hardy with respect to California winters.        -   Density.—Medium.        -   Form.—Conical, becoming elongated just before opening.        -   Pedicel.—Average length 5.2 mm. Average width 1.6 mm.            Surface — glabrous. Color varies from 5GY 7/8 to 5GY 5/10.        -   Color.—Varies from 5RP 9/2 to 5RP 6/12.-   Flowers:    -   -   Blooming period.—Date of First Bloom Feb. 18, 2014. Date of            Petal Fall Feb. 28, 2014, varies slightly with climatic            conditions.        -   Size.—Large, showy. Average height 22.0 mm. Average diameter            42.8 mm.        -   Petals.—Normally 5, alternately arranged to sepals. Size —            large. Average length 24.1 mm. Average width 19.8 mm. Form —            elliptical. Margin — sinuate. Arrangement — overlapping.            Petal apex — rounded. Petal base — truncated. Color varies            from 5RP 8/4 to 5RP 6/2. Both upper and lower surfaces            glabrous.        -   Sepals.—Normally 5, alternately arranged to petals. Size —            large. Average length 7.5 mm. Average width 7.0 mm. Shape —            ovate to triangular. Margin — entire. Apex — rounded to            triangular. Surface — upper surface glabrous, lower surface            pubescent. Color — upper surface varies from 5GY 6/10 to 5GY            5/10. Lower surface varies from 5GY 5/6 to 7.5RP 2/6.        -   Stamens.—Average number per flower 51. Average filament            length 16.2 mm. On average, the stamens are even with the            height of the petals. Filament color varies from N 9.5/            (white) to 2.5RP 4/8. Anther color varies from 5Y 8.5/10 to            2.5R 3/10.        -   Pollen.—Self fertile. Color varies from 2.5Y 7/12 to 5Y            7/12.        -   Pistil.—Number — normally 1. Average length 18.3 mm. Surface            — glabrous. Position of stigma an average of 1.9 mm below            the anthers. Color varies from 5GY 4/8 to 10Y 6/8.        -   Fragrance.—Wanting.        -   Color.—Varies from 5RP 8/4 to 5RP 6/12.        -   Pedicel.—Average length 5.7 mm. Average width 1.6 mm. Color            varies from 5GY 6/8 to 5GY 5/10.        -   Number flowers per flower bud.—Normally one.-   Fruit:    -   -   Maturity when described.—Firm ripe and ready for            consumption.        -   Date of first picking.—Aug. 15, 2014.        -   Date of last picking.—Aug. 22, 2014, varies slightly with            climatic conditions.        -   Size.—Large. Average diameter axially 69.7 mm. Average            transversely in suture plane 72.4 mm. Average weight 213.0            grams, varies slightly with fertility of the soil, amount of            thinning and climatic conditions.        -   Form.—Globose to elongated.        -   Suture.—Nearly smooth, extends from base to apex.        -   Ventral surface.—Nearly smooth.        -   Apex.—Rounded to slight pistil point.        -   Base.—Retuse.        -   Stem cavity.—Rounded to slightly elongated in the suture            plane. Average depth 11.2 mm. Average diameter 9.4 mm.-   Stem:    -   -   Size.—Small to medium. Average length 9.4 mm. Average            diameter 3.8 mm.        -   Color.—Varies from 2.5GY 6/8 to 5GY 7/6.-   Flesh:    -   -   Ripens.—Evenly.        -   Texture.—Firm, meaty.        -   Fibers.—Few, small, tender.        -   Firmness.—Good, comparable to other commercial varieties.        -   Aroma.—Slight.        -   Amydgalin.—Undetected.        -   Eating quality.—Excellent.        -   Flavor.—Excellent, mild, sweet, sub-acid flavor.        -   Juice.—Moderate amount, enhances flavor.        -   Acidity.—Not available.        -   Brix.—Average Brix 16.0°, varies slightly with amount of            fruit per tree and climatic conditions.        -   Color.—Varies from 7.5Y 9/2 to 10Y9/2.        -   Pit cavity.—Average length 39.7 mm. Average width 25.6 mm.            Average depth 11.6 mm. Color varies from 5R 3/10 to 7.5R            3/13.-   Skin:    -   -   Thickness.—Medium.        -   Surface.—Smooth.        -   Pubescence.—Wanting.        -   Tendency to crack.—None.        -   Color.—Ground color varies from 5Y 9/4 to 5Y 9/6. Overspread            with 5R 2/2 to 7.5R 3/12.        -   Tenacity.—Tenacious to flesh.        -   Astringency.—Undetected.-   Stone:    -   -   Type.—Clingstone, strong adherence to flesh.        -   Size.—Large. Average length 38.7 mm. Average width 24.6 mm.            Average thickness 20.6 mm.        -   Form.—Ovoid.        -   Base.—Flat.        -   Apex.—Pointed. Average length 3.0 mm.        -   Surface.—Pitted throughout, pits vary from round to            elongated.        -   Sides.—Unequal, one side extending further from the suture            plane.        -   Ridges.—Relatively smooth, extending from base to apex.        -   Tendency to split.—None.        -   Color.—Varies from 5R 2/2 to 7.5YR 3/4 when dry.-   Kernel:    -   -   Size.—Medium. Average length 17.2 mm. Average width 9.9 mm.            Average depth 6.4 mm.        -   Form.—Ovoid.        -   Viability.—Viable, complete embryo development.        -   Skin color.—Varies from 7.5YR 5/8 to 7.5YR 4/8.-   Use: Dessert. Market — local and long distance.-   Keeping quality: Good, held firm in cold storage at 38° to 42° F.    for 3 weeks without internal breakdown of flesh or appreciable loss    of flavor.-   Shipping quality: Good, minimal skin scarring or bruising of flesh    during picking, packing and shipping trials.-   Plant/fruit disease resistance/susceptibility: No specific testing    for relative plant/fruit disease resistance/susceptibility has been    designed. Under close observation during planting, growing, and    harvesting of fruit, under normal cultural and growing conditions    near Modesto, Calif., no particular plant/fruit disease resistance    or susceptibility has been observed. Any variety or selection    observed during indexing of plant characteristics with abnormal    fungus, bacterial, virus or insect susceptibility is destroyed and    eliminated from our breeding program. No atypical    resistances/susceptibilities have been noted under normal cultural    practices. The present new variety of nectarine tree, its flowers,    foliage and fruit herein described may vary in slight detail due to    climate, soil conditions and cultural practices under which the    variety may be grown. The present description is that of the variety    grown under the ecological conditions prevailing near Modesto,    Calif.

1. A new and distinct variety of nectarine tree (Prunus persica var.nucipersica), substantially as illustrated and described.